This application, in response to PA 95-070 "Brief Interventions to Prevent the Spread of AIDS," seeks funding for a five-year project to evaluate the efficacy of an interactive, individually tailored and computer-based HIV risk reduction intervention among people at high risk for contracting HIV. Efficient cost-effective methods for delivering primary HIV prevention interventions need to be developed, as budget crises impinge upon resources in public health clinic settings. Current technology allows behavioral science principles to be integrated into brief and engaging computer-delivered HIV risk reduction interventions. We believe that this type of intervention, in conjunction with abbreviated face-to-face counseling, can produce improved risk reduction effects at reduced cost when compared with standard, full-length face-to- face risk reduction counseling. To test this idea, we will use formative research and theory to develop an interactive, computerized, multimedia, individually tailored HIV risk-reduction intervention usable by people with all levels of computer experience. The computer software will use each participant's responses to provide detailed, individually tailored feedback and will assist the client in developing a risk reduction plan. All information will be presented on the computer and more detailed information will be printed as a personalized take-home risk reduction guide. We will recruit and enroll 600 at-risk participants (50% women) presenting for routine care at an inner-city public STI clinic and randomly assign participants to one of three intervention conditions: A 30-minute session of HIV risk reduction counseling based on the CDC client-centered counseling model (standard of care); the 30-minute computer-based intervention; or the same 30-minute computer intervention followed by 10 minutes of supplemental counseling, using the participant's questions and printed risk-reduction guide as stimuli. We will assess participants' HIV risk behavior and determinants, derived from the Information-Motivation-Behavioral Skills model of HIV preventive behavior at baseline, and at 1, 3, 6, and 12 month follow ups, using computerized assessments to reduce reporting biases. We hypothesize that the computerized counseling combined with abbreviated, supplemental counseling will result in greater sexual risk reduction than full-length standard counseling or the computerized intervention alone. We will also evaluate the cost-effectiveness of the interventions and expect that the combined intervention will be more cost-effective than standard counseling. Developing effective computerized interventions for HIV risk reduction at STI clinics and other HIV testing sites and supplementing them with abbreviated counseling may result in an efficient HIV prevention intervention that is feasible in real-world settings, and which can be used with many people at high risk for HIV infection - but which requires fewer resources to implement than standard counseling.